Wheelchair attachment

ABSTRACT

Wheelchair attachments, ordinarily installed in pairs, for enabling patients confined to wheelchairs to easily negotiate obstacles, such as curbs, in a conventional wheelchair having two small front wheels and two large rear wheels which the patient manually rotates to propel and maneuver the wheelchair. Each attachment includes an elevating member attachable to an axle of one of large rear wheels and having one or more prongs extending for a distance greater than the distance from the point at which the elevating member is attached to the wheelchair to the ground so that to mount a curb or similar obstacle the wheelchair can be made to stand on the elevating member with the large wheels elevated above the ground and against the curb or obstacle. The large wheels can then be manually rotated while against the curb to cause the wheelchair to climb the curb. The attachments of the invention must be used with a second attachment which includes an extendible wheel, or dolly, which is connectable to the wheelchair through supporting members and which can be manually extended backwards by the patient to a locked position. When both dollies of a pair of attachments are in this extended and locked position, the wheelchair can be tilted backwards manually to rest in a stable, tilted position on the two large wheels and the extended dollies or wheels with the two small front wheels, or casters, elevated. Curbs and other obstacles can then be simply negotiated in this tilted position by manually rotating the two large wheels so as to cause the wheelchair to stand on the pair of elevating members and then to climb the obstacle.

United States Patent [72] Inventors H.Franklin Coffey Albuquerque;Samuel T. Powers, Tijeras, both of, N. Mex. [21] Appl.No. 786,695 [22]Filed Dec.24,l968 [45] Patented May25,197l [73] Assignee LovelaceFoundation for Medical Education andResearch Albuquerque, N. Mex.

[54] WHEELCHAIR ATTACHMENT 26 Claims, 7 Drawing Figs.

[52] U.S.Cl 280/532, 280/528 [51] lnt.Cl B62b5/02 [50] FieldolSearch280/532, 5.28, 5.2,5.3, (DIG. 10); 297/(D1G. 4)

[56] References Cited UNlTED STATES PATENTS 865,514 9/1907 Mullenmeister280/5.32X 1,226,848 5/1917 Black 280/532 1,259,064 3/1918 Wolff....280/528 1,591,529 7/1926 Guerber... 280/474 2,701,005 2/1955 Bennett280/53 2,798,565 7/1957 Rosenthaletal. 180/65 3,304,094 2/1967 Wenger280/52 FOREIGN PATENTS 202,927 6/1907 Germany 280/532 324,830 9/1920Germany 280/528 Primary Examiner-Leo Friaglia AttorneyCushman, Darby &Cushman ABSTRACT: Wheelchair attachments, ordinarily installed in pairs,for enabling patients confined to wheelchairs to easily negotiateobstacles, such as curbs, in a conventional wheelchair having two smallfront wheels and two large rear wheels which the patient manuallyrotates to propel and maneuver the wheelchair. Each attachment includesan elevating member attachable to an axle of one of large rear wheelsand having one or more prongs extending for a distance greater than thedistance from the point at which the elevating member is attached to thewheelchair to the ground so that to mount a curb or similar obstacle thewheelchair can be made to stand on the elevating member with the largewheels elevated above the ground and against the curb or obstacle. Thelarge wheels can then be manually rotated while against the curb tocause the wheelchair to climb the curb. The attachments of the inventionmust be used with a second attachment which includes an extendiblewheel, or dolly, which is connectable to the wheelchair throughsupporting members and which can be manually extended backwards by thepatient to a locked position. When both dollies of a pair of attachmentsare in this extended and locked position, the wheelchair can be tiltedbackwards manually to rest in a stable, tilted position on the two largewheels and the extended dollies or wheels with the two small frontwheels, or casters, elevated. Curbs and other obstacles can then besimply negotiated in this tilted position by manually rotating the twolarge wheels so as to cause the wheelchair to stand on the pair ofelevating members and then to climb the obstacle.

PATENTEUMAQSIQH 3580591 SHEET 2 BF 3 INVENTORS 52 105; Pan 25 52@ Hi kwJOFFE y gwzw PATENTED mesmn 3580.591

' sum 3 or 3 INVENTORS' ywAwwmgwgiw TTORNEYJ WHEELCHAIR ATTACHMENT BRIEFDESCRIPTION OF THE PizioR ART AND SUMMARY OF THE INVENTION The inventionrelates to simple attachments to wheelchairs for enabling patientsconfined to wheelchairs to mount curbs and overcome other obstacles.

For the disabled individual, who has temporarily or permanently lost theuse of his legs and must depend upon mechanical, usually manuallyoperated, substitutes, such as wheelchairs, to move himself about, manyof the minor obstacles and obstructions, which thosefortunateindividuals who can walk manage without difficulty and usuallywithout notice, become extremely difficult to negotiate and, too often,insurmountable. Despite increased public awareness of the need toprovide special facilities, such as ramps, which those individuals whoare confined to wheelchairs can use, a short walk through any populatedarea quickly reveals many obstacles such as curbs, stairs, brokensidewalks and the like which, to an individual in a wheelchair, can makeeven a short trip a hazardous adventure. The present invention relatesto simple attachments which can be quickly and easily affixed toconventional existing wheelchairs and which enable a wheelchair confinedindividual to easily overcome minor obstacles without great effort orskill.

Many attempts have been made in the prior art to produce either awheelchair which can climb over or otherwise overcome obstacles orattachments to wheelchairs to enable such obstacles to be overcome. Forexample, the patents to Zamotin, U.S. Pat. No. 3,259,396, and Bennett etal. U.S. Pat. No. 2,701,005, show two types of wheelchairs of the priorart which purportedly can climb curbs and obstacles. However suchdevices have not found ready acceptance, perhaps because of theircomplexity or expense or some other problems. This invention relates tosimple, inexpensive, reliable attachments which can be easily andquickly affixed to wheelchairs and which not only perform satisfactorilybut which can be attached to conventional wheelchairs.

The wheelchair attachments of this invention are ordinarily used inpairs, each of the attachments being connected to one of the largewheels, which are conventionally manually rotated to propel thewheelchair, so that the wheelchair can be made to stand on theattachments with the large wheels clear of the ground and against a curbor similar obstacle so that these large wheels can then be employed toclimb the curb. In the embodiment set forth below, each attachmentincludes an elevating member which has one or more extending prongs andwhich is attachable to the axle of a large wheel so that the member ismanually rotatable about that axle but does no normally rotate with thewheel. The distance from the point of attachment of the member to theaxle to a small spiked wheel which is mounted for free rotation abouteach extending prong is designedly greater than the distance from thepoint of attachment to the ground so that when the member is manuallyrotated until one of the spiked wheels is against the ground and thenthe large wheels are further rotated, the wheelchair is caused to risestiltlike upon the two elevating members with the two large wheels offthe ground. If, in this elevated position, the large wheels are leaningagainst a curb or similar obstacle, the large wheels can be simplyrotated to cause the wheelchair to climb the curb or obstacle. If apronged member having two or more prongs is employed, the wheelchairprogressively is lifted from a first elevated position to a secondposition etc. in which the large wheels are successively further fromthe ground.

Each pair of elevating attachment is preferably employed with a secondpair of different attachments each of which is comprised on an elongatedmember, a dolly or wheel, a supporting connection made up of two rods,and means for connecting the elongated member and one of the rods to thewheelchair. The elongated member of each of a pair of these attachmentsis preferably attached to the wheelchair, in the embodiment set forthbelow, and particularly to each of the conventionally provided handgripsat the top of the wheelchair back. The length of this elongated memberis chosen to be less than the distance from the handgrip to the ground.Attached to the other end of each elongated member is the small wheel ordolly, which has been called a drop-back dolly, and which is similar tothe small permanently attached front wheel of the wheelchair itself.Also attached to a point between the ends of this elongated member isone of the rods of the supporting connection, which as mentioned above,is made up of the two rods serially connected together, and forming apivot at their point of connection. The other of the rods of thissupporting connection is then attached to the wheelchair and preferablyto the main rod which runs beneath and supports the wheelchair seat andback and which is attached to the axle of each large wheel. In a storageposition, each dolly or wheel is positioned roughly below handgrip towhich it is connected. This second pair of attachments is detailed in apatent application entitled WHEELCHAIR AT- TACHMENT Ser. No. 778,458,filed Nov. 25, I968.

To employ both pairs of attachments to mount an obstacle such as a curb,the dollies of each of the second pair of attachments are extendedbackwards by manually pushing downward on the pivot point between thetwo rods making up the supporting connection until the two rods lock bymeans of a scissor mechanism or the like. Next, both of the elevatingmembers are rotated until one of the spiked wheels, of each member, isin contact with the ground and in front of a large wheel. After thedollies or extendible wheels are so extended to the operative position,the wheelchair can be easily tilted backwards so that the front twowheels are elevated, and the wheelchair rests at an angle of about 45 ina stable position on the two large wheels and the two extended dollies.

The curb can now be mounted by moving the large wheels in the usualmanner until the large wheels rise on the elevating members and thelarge wheels are directly applied against the curb substantially abovethe base of the curb. The wheelchair now rests on the two dollies, thetwo large wheels and the two elevating members. The large wheels can nowbe manually rotated to climb the curb with the two backwardly extendingdollies or wheels remaining on the lower surface, and the elevatingmember being rotated by the curb to a position behind each large wheel.After the two large wheels are atop the curb or obstacle, the wheelchaircan now be tilted forward again by shifting the body weight so that thewheelchair returns to its normal upright position resting atop the curbon the two large wheels and the two small front wheels. Each of theextended dollies or wheels, which are once again elevated, can now bemanually rotated back to their storage position by manually releasingeach of the locking arrangements and pulling upward on each of the pivotpoints at which the two rods making up each supporting connection arelinked. The elevating members can then also be returned to their storagepositions by manual rotation about the axles of the large wheels.

Many other objects and purposes of this invention will be clear afterreading the following detailed description of the drawings.

A BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a conventionalwheelchair with the elevating attachments of this invention and theadditional pair of dollies shown in the storage position.

FIG. 2 shows a view of the attachment which enables the wheelchair to betilted backwards to a stable position.

FIG. 3 shows a front view of the elevating attachment.

FIG. 4 shows a side view of the elevating attachment.

FIG. 5 shows a view of a wheelchair with both pairs of attachments inthe operative position about to climb a curb.

FIG. 6 shows a view of a wheelchair with both pairs of attachments inthe midst of climbing a curb.

FIG. 7 shows a front view at another embodiment of the elevatingattachment with a single prong.

3 DETAILED DESCRIPTION or THE DRAWINGS Reference is now made to FIG. 1which shows a conventional wheelchair 20'with a pair of the elevatingattachments 21 of this invention added thereto, together with a pair ofattachments 50, to enable a wheelchair confined patient to negotiatecurbs, inclines, rough terrain, sand and rocks, and other obstacles witha minimum of difficulty or danger. The wheelchair 20 is conventionalwith a cloth back 22, a seat 24, armrests 26 and 27, a footrest 28,small front wheels 30 and 32, and manually operated large rear wheels 34and 36. The operator of the wheelchair 20 is supported by a frame whichincludes a pair of vertically disposed posts 40 and 42, which have acloth sheet or similar structure stretched between them to make up theback 22 and which extend downward and are permanently attached to theaxles 41 and 43, respectively, of the large wheels 34 and 36,respectively, and also to horizontally supporting members 44 and 46,respectively. The posts 40 and 42 terminate in handgrips 51 and 53 whichare provided so that the wheelchair 20 can be easily pushed by anotheras well as manually propelled by the operator. The horizontal members 44and 46 in turn support front posts 47 and 48 which connect to thearmrests 26 and 27, and which also support the struts which form theseat 24, In short, the wheelchair 20 shown in FIG. ll, is a simpleconventional wheelchair which is locomoted by the patient manuallyrotating the large wheels 34 and 36 so that the wheelchair and patientare propelled in the direction which the patient chooses. In addition,the wheelchair 20 shown in FIG. ll preferably is v collapsible forstorage and capable of being made ready for use from storage in a fewseconds.

As mentioned above, the pair of elevating attachments 2H, which functionin a stiltlike fashion to enable each of the large wheels 34 and 36 tobe lifted off the ground and applied to a curb or other obstacle at apoint considerably above the base of the curb, are respectively. In FIG.ll, both of the elevating attachments 211 are shown in the storageposition in which they in no way interfere with the normal operation ofthe wheelchair 20 nor rotate with the wheels 34 and 36. At the same timeboth of the attachments 21 much be capable of being manually rotated toan operative position where the spiked wheels 82 of the shorter prongs34 of the attachment 211 contact the ground, as shown in FIG. 5.

Any suitable means of connection between the wheelchair 20 and theattachments 21 can be used. However, as shown in FIGS. 1, 3 and 4 theattachment 21 of this embodiment is provided with two apertures 86 and33 connected by a slot 90 and the attachment 21 is connected to the axleM by removing the nonrotating bolt (not shown) which conventionallyholds the axle 41 in place, and running the bolt through the aperture 56or 8% through which it best fits so that the attachment 21 is heldfirmly but not immovably in place by the hub 94. Thus, the attachment isautomatically held in the storage position during normal movement of thewheelchair 20 while easily and manually rotatable to the operativeposition, shown in FIG. 5, for climbing curbs and other obstacles.

As can be seen in FIGS. 3 and 4, the attachment 21, which has beencalled a Curb Leveler, is made up of two extending prongs M and 94, bothof which emanate from an upper portion 96 from which the apertures 86and 83 and the slot 90 has been removed. For reasons which will becomeapparent below, the prong M is made deliberately shorter than the prong96.

Connected to the end of the prong 66 is a small spiked wheel 82 and tothe end of the prong 94 is another small spiked wheel 98. Each of thewheels 82 and 98 is mounted within holders W and W2 respectively, andthe holders we and 102 are permanently and immovably connected to theprongs 34 and 94 respectively, for example, by welding. Preferably, thewheels 82 and 98 are permitted rotate freely.

As can be seen in FIG. 41, the attachment 211 is bent outward from itspoint of connection to the axle M at a point roughly designated as we inorder to avoid contacting the rim or tire of the wheel 34. Further, alateral member R08 roughly parallels the rim of the wheel 34 andprovides additional support for the prongs 84 and 94. As shown in FIG.4, the member 105 curves about and protects the rims of the wheels 34and 36.

Each of the pair of attachments 21 is intended to be left in place whenthe wheelchair 20 is collapsed and stored and each can be quickly andsimply removed or attached. Further, no particular material ordimensions for the attachment 211 is required but, of course, theattachments 211 must be sufficiently strong to temporarily support atleast most of the weight of the wheelchair 20 as well as the weightsupported by the wheelchair 20.

Moreover, FIG. 11 also shows the two attachments 56 which are detailedin the aforementioned application Ser. No. 778,458, filed Nov. 25, 1968,attached to the conventional wheelchair 20. Each of these attachments 50is virtually identical and each can be left in position while thewheelchair 20 is collapsed for storage. Reference is now made to FIG. 2which shows in detail one of the attachments 50. As can be seen in FIG.2, the dolly or wheel 52, which is used to catch the wheelchair 20 whenit is tilted backward, is supported directly by an elongated member 54-which allows it to rotate freely in a conventional manner. The member 54is in turn pivotally attached to an upper member 58 which is preferablyattached to the wheelchair handle 51 or 53, as shown in FIG. I, bycutting or removing the end of the rubber or plastic grip whichconventionally covers the wheelchair handles 51 and 53 and inserting theconventional expansion lug 59 of the upper member 58 into the hollowhand grip or handle 5ll or 53. By tightening the nut 60 which fitswithin the expandable lug 53, the lug 58 and be expanded within thehollow handle SR or 53, and the attachment 50 firmly fixed to handle 51or 53.

A bracket 64 is shown attached to the member 54 in a position more thanmidway between the expansion lug 59 and the wheel or dolly 52. Fivotablyattached to this bracket 64 is a supporting connection 65 by which thewheel or dolly can be extended, made up of two separate rods 76 and 72.As can be seen in FIG. ll, the point of pivotal connection between rodsand 72 is within easy reach of the person in the wheelchair, so thatwhen the scissorlike mechanism 66 located at the connection between rods76 and 72 is manually pushed downward to cause the rods 76 and 72 toassume roughly a horizontal position, as shown in FIG. 5, the member 5 1and wheel 52 are pivoted about the point 80 at which they attach to theupper member 511 and the dolly or wheel 52 moves backward to theoperative position. In this embodiment, the rods 76 and 72 as connectedto the scissor mechanism 66 trace an arc from about 25 to over and lockin place at about When locked, the attachment 50 will not collapse toits original storage position until the operator manually pulls upwardon the scissor mechanism 66. Thus, there is virtually no possibilitythat the attachment 50 will collapse when the wheelchair is tiltedbackwards at approximately 45.

The rod 72, and thus the connection 65, is attached to a short bracket74, as shown in FIG. ll, which is in turn connected to wheelchair 26 forexample, by removing the axle nuts and bolts (not shown) that hold thewheel 34 and positioning the bracket 74 so that the hole 76 is alignedwith the boltholes by which the wheel 36 is attached to its axle Ill.The axle bolts and nuts can then be reapplied tightly so that thebracket 745 is firmly and securely attached to the axle All in themanner shown in FIG. ll.

Reference is now made to FIG. 5 which shows the wheelchair 2th in aposition about to mount the curb 75 with the pair of wheelchairattachments 56 locked in the stable extended position and the wheelchair26 thus supported by both the large wheels 32 and 3d and two dollies orwheels 52, and with the pair of elevating attachments Zll each in theoperating position so that the spiked wheels 82 are in contact with theground. As is apparent from FIGS. 1 and 5, each of the wheels 52, inboth the storage and extended operative position is elevated aconsiderable distance above the ground when the wheelchair 2t restsupright on the two front wheels 3.6 and 32 and the two large rear wheels36 and 36. Thus, when the wheelchair 20 is manually tilted backwards torest on the two wheels 52 and the large wheels 34 and 36, the smallfront wheels 30 and 32 are likewise elevated and as shown in FIG. 5, thefront wheels 30 and 32 can then be placed atop or above an obstacle suchas the curb 79 shown in FIG. 5, by rolling the wheelchair 20 forward inthe tilted position until the large wheels 36 and 36 are at a shortdistance from the base of the curb 79. The angle between the tiltedwheelchair 20 and the ground can, of course, be simply controlled bychanging the length of member '54 and rods 70 and 72 to change thedistance from the extended wheels 52 to the wheelchair 20 and the normalupright distance from the extended wheels 52 to the ground. A tiltingangle of about 45 is shown in FIG. 5, and this angle has been foundquite satisfactory. At this angle, most patients using the second pairof attachments only with practice have been able to climb a 4-inch curb,to dismount a 15-inch curb, to go over parking lot dividers, and toovercome most common obstacles in streets, highways and sidewalks. Byusing both the elevating attachments and the second pair of attachments,a 9-inch curb can be climbed, a l5-inch curb can be dismounted and anobstacle 9 to 10 inches high and 8 to 12 inches wide can be easilyovercome.

The attachments 21 can be manually rotated to their operative positionas shown in FIG. 5 from the storage position shown in FIG. 1, eitherbefore or after the wheelchair 21 is tilted to the stable tiltedposition. Such rotation of the attachment 21 can be accomplished merelyby grasping the attachments 21 and pushing downward until the wheels 32each touch the ground.

To assume the tilted position, the individual in the wheelchair firstmoves both of the wheels 52 to the extended position by pushing downwardon each of the scissor mechanism 66 until each of the attachments Stl isfirmly locked in place. Then the wheelchair is tilted backwards by theoperator until the wheelchair 20 rests on the rear wheels 34 and 36 andboth of the wheels 52. This tilting can be accomplished in any manner,for example, by producing slight backward momentum, then quickly andsmoothly jerking the large wheels 34 and 36 forward and at the same timethrowing the body weight backwards. With practice, this maneuver can beaccomplished without substantial effort and without strain to thedollies or wheels 52 or the front wheels 30 and 32.

To climb the curb from this tilted position with the attachments 21 inthe operative position, the patient first grasps two large wheels 34 and36 and rotates them to cause the wheelchair 20 to stand on the wheels 82of the short prongs 84 of both attachments 21 with the wheels 34 and 36off the ground. The forward momentum of the wheelchair 20 next causesthe wheelchair to rise still further onto both of the wheels 98 of thelonger prongs 9d. If the patient has gauged his initial distance fromthe curb correctly, the large wheels 34 and 36 will now contact the curb79 at a location above the base as shown in FIG. 7, preferably with theattachments 21 leaning slightly forward to throw considerable weightonto the wheels 34 and 36. The wheelchair operator now merely continuesto rotate the large wheels 34 and 36 manually to cause the wheels 34 and36 to climb the curb 79 and, at the same time, drag the wheels 52slightly forward. When done with a smooth, continuous motion from aproper starting position, the climb can be accomplished easily andwithout strain on either the operator, the wheelchair 20, or theattachments 21 and 50.

When the wheels 34 and 36 are atop the curb 79, the wheelchair operatorcan now tilt the wheelchair 20 forward, for example by repeating inreverse the maneuver used to assume the backward tilted position, tocause the new elevated front wheels $0 and 32 to resume contact with theground and the wheels 52 to again become elevated. The wheelchair 20 isnow safely atop the curb 79 and in the normal upright position restingon wheels 31), 32, M and 36 with the wheels 52 elevated. The wheels 52can now be returned to their storage position by manually pulling upwardon each of the scissor mechanisms 66 to rotate each of the wheels 52back to the position shown in FIG. 1. Similarly, the attachments 21 canbe manually rotated back to the storage position shown in FIG. 1.

Of course, it is not necessary that the attachments 21 have anyparticular number of prongs. More than two can be employed if desirableand in FIG. 7 an attachment 21 with a single prong 112 and a spikedwheel 114 is shown. Climbing with a single prong is, of course,substantially the same as climbing with a double prong as describedabove, except that the height with can be reached is necessarily less.

Experienced and skilled wheelchair operators, of course, have heretoforebeen able to accomplish a similar climbing maneuver without assistingdevices, such as the attachments 50, simply by balancing on the twolarge wheels 34 and 36 although, of course, risking the substantialdanger of falling over backwards with resulting damage to wheelchair andoperator. The attachments 21 can be used by such people to increase theheight of the curb which can be climbed. However, since such balancingtakes time and skill to perfect, as well as being dangerous, theattachments 21 are most advantageously employed with other attachmentssuch as the attachments 50 which any individual can learn to use safelyand effectively in a very short length of time. The ability to correctlyposition the the wheels 34 and 36 the right distance from the base ofthe curb '79 can be quickly learned and failure to so position or tomake the climb do not result in a dangerous fall but only a safe descentafter which another attempt can be made. Thus, the attachments 50 whenused with the elevating attachments 21 enable the above-describedclimbing operation to be done with complete safety and ease. Even shouldone of the attachments 5f) fail during climbing, tests have indicatedthat either of the attachments 50 along is sufficient to support thewheelchair 20. The only real source of danger is the possible humanerror of forgetting to extend either of the wheels 52 before thewheelchair 20 is tilted.

As mentioned, the attachments 21 and Stl can be used alone as well as incombination. For example, the attachments 21 can be used alone in apole-vaulting fashion to jump over obstacles such as broken sidewalks,soft ground, etc. However, since many maneuvers required or are bestperformed with both pairs of attachments 50 and 21, the wheelchair 20preferably is equipped with both especially since using both attachments50 and 21 to climb a curb substantially increases the height of the curbwhich can be climbed over the height which can be climbed with eitherthe attachments 50 or attachments 21 alone.

Of course, the patient cannot only mount curbs but can overcomevirtually any type of minor obstacle with the attachments 50, eitheralone or in combination with the attachments 22. Use of the attachments50 cases even movement over sand and rough terrain, which is ordinarilyvery clifflcult because of the tendency of the small front wheels 30 and32 to plow and pitch the operator forward. By assuming the tiltedposition while moving over sand and rough ground, the large rear wheels34 and 26 are converted into the lead wheels and progress is thussubstantially easier. Even if the wheelchair 20 veers off its intendedcourse due to the fact that one of the wheels 52 is deeper in sand orhits a rock or hole, the patient can simply continue by lifting thewheels 52 a few inches off the ground and at the same time manuallyturning his wheelchair 20 a few degrees with his large wheels 34 and 36until he can resume his intended course. With this maneuver, which canbe quickly and simply learned, a wheelchair confined patient can makeeven a turn or reverse his direction by with case.

Although not especially designed for this purpose, it is believed thatuse of the attachments 50 will reduce the prevalence of pressure ulcersover the ischia in wheelchairconfined individuals. By resuming thetilted position for a few minutes each hour, it has been demonstratedthat pressures on critical regions of wheelchair-confined individualsare reduced by about 35 percent so that even those patients who mustspend l0 to 15 hours a day in their wheelchairs can avoid or at leastreduce the chances of incurring this common difficulty. Further, theattachments 50 permit a conventional wheelchair to be converted into acomfortable lounge chair simply by resuming the tilted position.

Adding to their advantages is the ease with which both the attachments50 and 2ll can be removed from one wheelchair and transferred to anotherwheelchair. The attachments 50 can be removed from one wheelchair 2t)and transferred to another in about 10 minutes, and removal and additionof the attachments 21 can also be rapidly accomplished. Of course, itmay be desirable to permanently fix the attachments 50 to the wheelchair20 or to construct a wheelchair with the attachments 50 as a permanentpart thereof. Likewise, it may be desirable to build a wheelchair withthe attachments 21 permanently affixed or to permanently attach theattachments 21 to an existing conventional wheelchair. However, untilall wheelchairs are so equipped, the adaptability of the attachments 50and 2ll to any conventional wheelchair makes them especially useful.

Further, the inherent simplicity of both the attachment 50 andattachments 2B in comparison to the functions which they perform makesthem both inexpensive and economical. Since no major alteration of thewheelchair to which they are attached is necessary to even desirable,the total cost of the attachments t) and H to the wheelchair-confinedindividual is nominal especially compared to the mobile capability whichthey give him. Their simplicity also virtually guarantees trouble-freeoperation and precludes expensive maintenance. In short, the attachments50 and 21 are both simple, inexpensive, reliable devices, easily andquickly attachable to conventional wheelchairs and capable of enabling awheelchair-confined individual to overcome common obstacles and movefreely about his environment.

As mentioned above, the attachments 211 can also be permanentlyconnected to the wheelchair or can be removable as in the embodiment setforth above. Further, the attachments 21 and the attachments 50 whilepreferably used together can each be used separately. Many changes andmodifications in the examples set forth above will be apparent to anyone of ordinary skill in the art and the invention is intended to belimited only by the following claims.

We claim:

ll. A wheelchair attachment for overcoming obstacles in a wheelchairwith a pair of driving wheels, each having an axle, comprising meansmountable on said wheelchair for enabling said wheels to be elevatedabove the ground including stilt means with a member attached to saidaxle of one of said wheels having a length greater than the distancefrom said axle to the ground and a spiked wheel connected to the end ofsaid member which contacts the ground, said member being manuallyrotatable from a storage position to an operative position in contactwith the ground and further rotatable in response to manual rotation ofsaid wheels to cause said wheels to be elevated.

2. An attachment as in claim 1 wherein said stilt means includes amember and spiked wheel attached to each said axle.

3. An attachment as in claim 2 wherein said member terminates in asingle end which contacts the ground.

4. An attachment as in claim 2 wherein said member terminates in twoends at different distances from the point of said member attached tosaid axle.

5. In combination, wheelchair attachments for a wheelchair with a pairof driving wheels comprising,

wheelchair-supporting means mountable behind said wheelchair so thatsaid wheelchair can be tilted backwards to a stable tilted position inwhich at least a portion of the weight of said wheelchair and the weightsupported by said wheelchair is supported by said supporting means, and

means mountable on said wheelchair for enabling said wheels to beelevated above the ground while said wheelchair is tilted backwards.

6. An attachment as in claim 5 wherein said attachments are forovercoming obstacles and wherein said supporting means includes meansfor holding said supporting means in position supporting said wheelchairduring the time said wheelchair is operated to overcome said obstacle,and said enabling means includes stilt means manually rotatable from astorage to a operative position and further rotatable in response tomanual rotation of said wheels to cause said wheels to be elevated.

7. An attachment as in claim K wherein said wheelchair includes a pairof small front wheels and said driving wheels include a pair of largerear wheels which are manually operated to move said wheelchair, whereinsaid supporting means includes at least a single wheel and wherein saidwheelchair is operated to overcome said obstacle by manually rotatingsaid large rear wheels.

8. An attachment as in claim 7 wherein said supporting means includes atleast two of said single wheels, each independently attached to saidwheelchair.

9. An attachment as in claim a including manually operable means formoving each of said single wheels from a storage position to anoperative position in which said wheelchair can be tilted backwards tosaid stable position and for moving each of said single wheels to saidstorage from said operative position.

llll. An attachment as in claim 9 including means to lock each of saidsingle wheels in said operative position.

ll. An attachment as in claim 10 wherein said supporting means includesa first member connected at one end to one of said single wheels to asto allow said one single wheel to rotate freely and at the other endpivotably connected to said wheelchair, said first member having alength less than the distance from the point said first member isattached to said wheelchair to the ground when said wheelchair is in theupright position, a second member pivotably connected one end to saidfirst member between said ends, and a third member pivotably attached atone end to the other end of said second member and pivotably connectedto said wheelchair at a point lower than the point of connection to saidfirst member at the other end of said third member so that said firstmember can be pivoted about its point of connection to said wheelchairto extend said one single wheel backwards by manually pushing downwardon the point of connection between said second and third members.

112. An attachment as in claim lill wherein each of said wheels has anaxle and said stilt means includes a member attachable to said axle ofone of said wheels and having a length greater than the distance fromsaid axle to the ground.

13. An attachment as in claim 12 including a spiked wheel connected toan end of said member which contacts the ground.

M. An attachment as in claim 113 wherein said stilt means includes amember and spiked wheel attached to each said axle.

15. An attachment as in claim 1 wherein said member terminates in asingle end which contacts the ground.

116. An attachment as in claim 15 wherein said member terminates in twoends at different distances from the point of said member attached tosaid axle.

17. A wheelchair comprising:

a pair of small front wheels,

a pair of manually rotatable rear wheels,

frame means connected to said front and rear wheels and forming a seat,

wheelchair-supporting means mounted on said frame means including firstand second supporting wheels, means attaching said supporting wheels tosaid frame means and means for moving said supporting wheels from astorage position with said supporting wheels above the ground andadjacent said rear wheels a tilted position rearwardly spaced from saidrear wheels and in which at least a portion of the weight of saidwheelchair and the weight supported by said wheelchair is supported bysaid supporting means, and

means mounted on said wheelchair for enablingsaid rear wheels to beelevated above the ground. I

18. A wheelchair as in claim 17 wherein said supporting means includes apair of extendible wheels.

19. A wheelchair as in claim 18 wherein said supporting means is movablefrom a storage to an operative position and from said operative to saidstorage position and, wherein said enabling means is movable to astorage to an operative position and from an operative to a storageposition.

20. A method of operating a wheelchair driven by a pair of wheels toovercome obstacles comprising the steps of tilting the wheelchairbackwards until the wheelchair is in a stable tilted position in whichthe weight of the wheelchair and the weight supported by the wheelchairis at least partially supported by supporting means mounted behind saidwheelchair elevating the driving wheels above the ground and thenagainst the obstacle to be overcome, and

manipulating said wheelchair in said stable tilted elevated position toclimb said obstacle.

21. A method as in claim 20 including the step of manually shifting saidsupporting means from a storage to an operative position.

22. A method as in claim 21 including the step of manually shifting saidsupporting means from said operative to said storage position after saidobstacle has been overcome.

23. A method of overcoming obstacles in a wheelchair having a pair ofsmall front wheels, a pair of large manually rotatable rear wheels, apair of extendible wheels manually movable from a storage-position to astable, operative position in which said extendible wheels are behindsaid rear wheels and are elevated above the ground when said wheelchairrests on said front and rear wheels and stilt means mounted on the axleof said large wheels and having a member whose length is greater thanthe distance from said axle to the ground so that said large wheels canbe elevated above the ground by rotating the large wheels when the stiltmeans is placed in contact of the ground in front of the large wheelcomprising the steps of:

manually moving said extendible wheels from said storage to saidoperative position,

manually moving said stilt means from said storage to said operativeposition,

manually tilting said wheelchair backwards, to a stable tilted positionin which said wheelchair rests on said extendible wheels and said rearwheels,

manually rotating said rear wheels to cause said large wheels to beelevated and to contact said obstacle above said ground,

manually continuing the rotation of said rear wheel to cause saidwheelchair to overcome said obstacle,

manually returning said extendible wheels to said storage position aftersaid obstacle has been overcome, and manually returning said stilt meansto said storage position after said obstacle has been overcome.

24. A method of overcoming obstacles in a wheelchair having two drivingwheels and an elevating member attached to each of said wheels,rotatable about the center of said wheels and having a length greaterthan the point of attachment of said member to said wheel to the groundso that said wheelchair can be made to rise, with said wheels elevated,onto said members comprising the steps of:

manually rotating both of said members so that said members contact theground,

rotating said wheels so that said wheels are elevated above the groundand then moved into contact with said obstacle, and

continuing rotating said wheels so that said wheelchair climbs saidobstacle.

25. A wheelchair attachment for overcoming obstacles in a wheelchairwith a pair of driving wheels, each having an axle, comprising meansmountable on said wheelchair for enabling said wheels to be elevatedabove the ground including stilt means with a member attached to saidaxle of one of said wheels having a length greater than the distancefrom said axle to the ground and a wheel connected to the end of saidmember WhlCl'l contacts the ground, said member being manually rotatablefrom a storage position to an operative position in contact with theground and further rotatable in response to manual rotation of saidwheels to cause said wheels to be elevated.

26. An attachment for a wheelchair with a pair of driving wheelsattached to an axle comprising means mountable on said wheelchair forenabling said wheels to be elevated above the ground for overcomingobstacles, said enabling means including stilt means with a memberattached to said axle and terminating at two ends at different distancesfrom the point of attachment of said member to said axle, said memberbeing manually rotatable from a storage position to an operativeposition with one of said ends in contact with the ground and furtherrotatable in response to manual rotation of said wheels to cause saidwheels to be elevated with the other of said ends in contact with theground.

1. A wheelchair attachment for overcoming obstacles in a wheelchair witha pair of driving wheels, each having an axle, comprising meansmountable on said wheelchair for enabling said wheels to be elevatedabove the ground including stilt means with a member attached to saidaxle of one of said wheels having a length greater than the distancefrom said axle to the ground and a spiked wheel connected to the end ofsaid member which contacts the ground, said member being manuallyrotatable from a storage position to an operative position in contactwith the ground and further rotatable in response to manual rotation ofsaid wheels to cause said wheels to be elevated.
 2. An attachment as inclaim 1 wherein said stilt means includes a member and spiked wheelattached to each said axle.
 3. An attachment as in claim 2 wherein saidmember terminates in a single end which contacts the ground.
 4. Anattachment as in claim 2 wherein said member terminates in two ends atdifferent distances from the point of said member attached to said axle.5. In combination, wheelchair attachments for a wheelchair with a pairof driving wheels comprising, wheelchair-supporting means mountablebehind said wheelchair so that said wheelchair can be tilted backwardsto a stable tilted position in which at least a portion of the weight ofsaid wheelchair and the weight supported by said wheelchair is supportedby said supporting means, and means mountable on said wheelchair forenabling said wheels to be elevated above the ground while saidwheelchair is tilted backwards.
 6. An attachment as in claim 5 whereinsaid attachments are for overcoming obstacles and wherein saidsupporting means includes means for holding said supporting means inposition supporting saiD wheelchair during the time said wheelchair isoperated to overcome said obstacle, and said enabling means includesstilt means manually rotatable from a storage to a operative positionand further rotatable in response to manual rotation of said wheels tocause said wheels to be elevated.
 7. An attachment as in claim 1 whereinsaid wheelchair includes a pair of small front wheels and said drivingwheels include a pair of large rear wheels which are manually operatedto move said wheelchair, wherein said supporting means includes at leasta single wheel and wherein said wheelchair is operated to overcome saidobstacle by manually rotating said large rear wheels.
 8. An attachmentas in claim 7 wherein said supporting means includes at least two ofsaid single wheels, each independently attached to said wheelchair. 9.An attachment as in claim 8 including manually operable means for movingeach of said single wheels from a storage position to an operativeposition in which said wheelchair can be tilted backwards to said stableposition and for moving each of said single wheels to said storage fromsaid operative position.
 10. An attachment as in claim 9 including meansto lock each of said single wheels in said operative position.
 11. Anattachment as in claim 10 wherein said supporting means includes a firstmember connected at one end to one of said single wheels to as to allowsaid one single wheel to rotate freely and at the other end pivotablyconnected to said wheelchair, said first member having a length lessthan the distance from the point said first member is attached to saidwheelchair to the ground when said wheelchair is in the uprightposition, a second member pivotably connected one end to said firstmember between said ends, and a third member pivotably attached at oneend to the other end of said second member and pivotably connected tosaid wheelchair at a point lower than the point of connection to saidfirst member at the other end of said third member so that said firstmember can be pivoted about its point of connection to said wheelchairto extend said one single wheel backwards by manually pushing downwardon the point of connection between said second and third members.
 12. Anattachment as in claim 11 wherein each of said wheels has an axle andsaid stilt means includes a member attachable to said axle of one ofsaid wheels and having a length greater than the distance from said axleto the ground.
 13. An attachment as in claim 12 including a spiked wheelconnected to an end of said member which contacts the ground.
 14. Anattachment as in claim 13 wherein said stilt means includes a member andspiked wheel attached to each said axle.
 15. An attachment as in claim14 wherein said member terminates in a single end which contacts theground.
 16. An attachment as in claim 15 wherein said member terminatesin two ends at different distances from the point of said memberattached to said axle.
 17. A wheelchair comprising: a pair of smallfront wheels, a pair of manually rotatable rear wheels, frame meansconnected to said front and rear wheels and forming a seat,wheelchair-supporting means mounted on said frame means including firstand second supporting wheels, means attaching said supporting wheels tosaid frame means and means for moving said supporting wheels from astorage position with said supporting wheels above the ground andadjacent said rear wheels a tilted position rearwardly spaced from saidrear wheels and in which at least a portion of the weight of saidwheelchair and the weight supported by said wheelchair is supported bysaid supporting means, and means mounted on said wheelchair for enablingsaid rear wheels to be elevated above the ground.
 18. A wheelchair as inclaim 17 wherein said supporting means includes a pair of extendiblewheels.
 19. A wheelchair as in claim 18 wherein said supporting means ismovable from a storage to an operative position and from said operativEto said storage position and, wherein said enabling means is movable toa storage to an operative position and from an operative to a storageposition.
 20. A method of operating a wheelchair driven by a pair ofwheels to overcome obstacles comprising the steps of tilting thewheelchair backwards until the wheelchair is in a stable tilted positionin which the weight of the wheelchair and the weight supported by thewheelchair is at least partially supported by supporting means mountedbehind said wheelchair elevating the driving wheels above the ground andthen against the obstacle to be overcome, and manipulating saidwheelchair in said stable tilted elevated position to climb saidobstacle.
 21. A method as in claim 20 including the step of manuallyshifting said supporting means from a storage to an operative position.22. A method as in claim 21 including the step of manually shifting saidsupporting means from said operative to said storage position after saidobstacle has been overcome.
 23. A method of overcoming obstacles in awheelchair having a pair of small front wheels, a pair of large manuallyrotatable rear wheels, a pair of extendible wheels manually movable froma storage position to a stable, operative position in which saidextendible wheels are behind said rear wheels and are elevated above theground when said wheelchair rests on said front and rear wheels andstilt means mounted on the axle of said large wheels and having a memberwhose length is greater than the distance from said axle to the groundso that said large wheels can be elevated above the ground by rotatingthe large wheels when the stilt means is placed in contact of the groundin front of the large wheel comprising the steps of: manually movingsaid extendible wheels from said storage to said operative position,manually moving said stilt means from said storage to said operativeposition, manually tilting said wheelchair backwards, to a stable tiltedposition in which said wheelchair rests on said extendible wheels andsaid rear wheels, manually rotating said rear wheels to cause said largewheels to be elevated and to contact said obstacle above said ground,manually continuing the rotation of said rear wheel to cause saidwheelchair to overcome said obstacle, manually returning said extendiblewheels to said storage position after said obstacle has been overcome,and manually returning said stilt means to said storage position aftersaid obstacle has been overcome.
 24. A method of overcoming obstacles ina wheelchair having two driving wheels and an elevating member attachedto each of said wheels, rotatable about the center of said wheels andhaving a length greater than the point of attachment of said member tosaid wheel to the ground so that said wheelchair can be made to rise,with said wheels elevated, onto said members comprising the steps of:manually rotating both of said members so that said members contact theground, rotating said wheels so that said wheels are elevated above theground and then moved into contact with said obstacle, and continuingrotating said wheels so that said wheelchair climbs said obstacle.
 25. Awheelchair attachment for overcoming obstacles in a wheelchair with apair of driving wheels, each having an axle, comprising means mountableon said wheelchair for enabling said wheels to be elevated above theground including stilt means with a member attached to said axle of oneof said wheels having a length greater than the distance from said axleto the ground and a wheel connected to the end of said member whichcontacts the ground, said member being manually rotatable from a storageposition to an operative position in contact with the ground and furtherrotatable in response to manual rotation of said wheels to cause saidwheels to be elevated.
 26. An attachment for a wheelchair with a pair ofdriving wheels attached to an axle comprising means mountabLe on saidwheelchair for enabling said wheels to be elevated above the ground forovercoming obstacles, said enabling means including stilt means with amember attached to said axle and terminating at two ends at differentdistances from the point of attachment of said member to said axle, saidmember being manually rotatable from a storage position to an operativeposition with one of said ends in contact with the ground and furtherrotatable in response to manual rotation of said wheels to cause saidwheels to be elevated with the other of said ends in contact with theground.